LS1 245cc Mongoose Competition Head

Sale: $2,781.00
Save: -3% off

245cc LSX "Mongoose" Competition Head

Our Max Effort Cathedral Port Offering

LSX 245cc Mongoose Cylinder Head
Click to enlarge

AFR's 245cc LSX "Competition" ported heads feature 100% CNC ported intake, exhaust & chambers, A356 aluminum castings, Titanium retainers and high quality components throughout. Recommended for race applications or radical "Pro Street" style builds with displacements up to 454 cubic inches, operating up to 6800 RPM. Requires minimum 4.000 bore size for intake valve clearance. Part numbers with an asterisk are legal for 2005 and older emissions controlled vehicles under CARB EO #D-250-4. Component upgrade and machining options are available to customize AFR Heads to your specific build, please email call or chat for your specific needs. AFR PN: 1680 and 1690 (64 or 72cc chambers, your choice)

245cc Large Bore LSX Aluminum Cylinder Head Flow Chart

Tested on 4.155 bore

225cc LS1 Big Bore Flow Chart 

Basic Package Components

100% CNC Ported Combustion Chambers

100% CNC Ported Exhaust Ports

100% CNC Ported Intake Ports

Competition 5-angle Valve Job

AFR #72118mm Bead Lock Intake Valve, 2.165" x 4.900" Overall Valve Length

AFR #72288mm Bead Lock Exhaust Valve, 1.600" x 4.900" Overall Valve Length

AFR #8019PAC Racing Spring 1.270" OD Hydraulic Roller Dual Valve Spring, 155 lbs. on seat, Max RPM 7000-7200

AFR #85127° Titanium Retainers 1.245" O.D x .885" I.D x .655" I.D

AFR #9007*7° Bead Lock Valve Keepers

AFR #6612Viton Valve Seals .600" O.D x .495" I.D

AFR #8042Hardened Valve Spring O.D Locator 1.380" O.D x .570" I.D

AFR #9060Ductile Iron Intake Valve Seats 2.200" O.D x 1.750" I.D x .375" Deep

AFR #9069Ductile Iron Exhaust Valve Seats 1.650" O.D x 1.350" I.D x .375" Deep

AFR #90518 mm Bronze Valve Guides .502" O.D x 2.100" O.A.L

*LSX bead locks and aftermarket bead locks are not interchangeable. GM made their bead lock radius and depth different. AFR locks are the same as GM LSX.


Specifications & Features:

A356 AluminumMaterial

245ccIntake Port Volume

3.315"H x 1.145"W x 11/32 top 13/32 bottomIntake Port Dimension

StockIntake Port Location

88ccExhaust Port Volume

1.495" H x 1.730" WExhaust Port Dimension

StockExhaust Port Location

65cc or 73ccCombustion Chamber Size

Center BoltValve Cover Bolt Pattern

15°Valve Angle

1.510" O.DValve Spring Pocket Diameter

1.525" O.DMax Valve Spring Pocket Machining

.750"Deck Thickness

4.000"Minimum Bore Diameter

.006" per cc 58cc MaximumFlat Mill - 65cc chamber

.006" per cc 65cc MaximumFlat Mill - 73cc chamber

2.680 sq. in.Minimum Cross Sectional Area

14mm x .750" w/Gasket SeatSpark Plug Dimensions

D-250-4Carb EO#


Recommended Components:

GM or FASTIntake Port Gasket

GM #12558573Exhaust Port Gasket

AFR #6845Head Gasket, Cometic 4.200 .040"

AFR #6330Head Bolts (97-03), ARP 134-3609

AFR #6331Head Studs (97-03), ARP 234-4110

AFR #6334Head Bolts (04+), ARP 134-3610

AFR #6335Head Studs (04+), ARP 234-4317

AFR #6320Head Bolt Washers, Manley

FAST 90mm, 92mm, or 102mmSuggested Manifold

NGK TR55Spark Plug Starting Range

Add to Cart:

  • Model: AFR1680
  • Shipping Weight: 68lbs